There are other risk factors for cancer that are unrelated to your stage of life, your genetics, or your lifestyle. Some of them are less noticeable, and sometimes less visible in your day-to-day life.
These factors include:
- Infections: Infections, and infectious diseases, cause up to 15-20 percent of the cancer cases reported around the world. The percentages are somewhat lower in the United States, but infection can still be a critical cancer risk factor in America. Some infections weaken the natural immune system that protects your body from cancers, and some infections can directly impact genes that control cell growth, ultimately increasing the risk of cancer. Human papillomavirus has been linked to cancers of the cervix, penis, vagina, and anus. Hepatitis B and hepatitis C have been related to liver cancer, and Epstein-Barr virus increases the risk of lymphoma. It may be reassuring to know that most people with these infections will never develop cancer.
- UV Radiation: Ultraviolent radiation (UV radiation) is a known cause of cancer. You are exposed to the primary source of UV radiation to some degree almost every day. The good news is that only a small percentage of the sun's rays are UV rays, and because they lack the energy to penetrate your body, the only cancer risk they represent is to your skin. There are also UV rays present in artificial tanning bed technologies. Repeated exposure to tanning beds can also increase your risk of skin cancer. Basal cell and squamous cell cancers are the most common skin cancers. They are usually associated with prolonged exposure of certain body parts to direct sunlight, a history of sunburn experiences over time, and in general a lifetime of skin exposure to either the sun or tanning beds. Melanoma, which is more rare but also more serious, has also been linked to consistent sun exposure over time and a history of serious sunburns.
- Environmental Factors: All substances that have been found to cause cancer - also known as carcinogens - are elements that you should avoid. The presence of carcinogens does not necessarily lead to the development of cancer, but it does increase your risk of doing so. As you inhale (and you do so approximately 20,000 times a day), keep in mind that respiratory exposure to asbestos, and even to prolonged air pollution, has been linked to the development of lung cancer. If you are somehow drinking unfiltered water that contains significant amounts of arsenic, you are increasing your risk of skin, bladder, and lung cancers. For people who work and live in agricultural communities, some combination of exposure to pesticides, fertilizers and animal infections may explain a higher incidence of leukemia, non-Hodgkin's lymphoma and other cancers.